Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that the car's computer has detected a problem with how the intake valve for cylinder 6 is working. It's like one of the doors in a six-door house isn't opening or closing properly.
The engine control module (ECM) monitors the performance of the intake valve for cylinder 6. If it detects that the valve isn't opening or closing as expected, it triggers this code.
P349D indicates a problem with the deactivation mechanism or performance of the intake valve on cylinder 6. This could be due to a mechanical failure, an electrical issue, or a problem with the oil control solenoid responsible for valve timing.
• Check Engine Light on
• Reduced engine performance
• Increased fuel consumption
• Faulty intake valve
• Oil control solenoid malfunction
• Wiring or connector issues
ECM: Engine Control Module, the computer that controls engine functions.
Solenoid: An electromechanical device that controls the flow of fluid or air.
• Check for any other related codes.
• Inspect the wiring and connectors for damage.
• Test the oil control solenoid for proper operation.
• Replace faulty intake valve or components.
• Repair or replace damaged wiring/connectors.
• Replace the oil control solenoid if faulty.
• OBD-II scanner
• Multimeter
• Socket set
$200 - $600
Moderate
• Chevrolet Silverado
• GMC Sierra
• Cadillac Escalade
• Regular oil changes
• Routine engine maintenance
• Inspecting electrical connections periodically
Engine Performance
• Address the issue promptly to avoid further engine damage.
• Consult a professional mechanic if unsure about repairs.
Check with your vehicle manufacturer for warranty coverage on engine components.
This code is commonly associated with vehicles using cylinder deactivation technology to improve fuel efficiency.
Moderate – Should be addressed soon to prevent potential engine damage.
Driving with a malfunctioning engine can lead to safety issues and increased emissions.
• Engine at operating temperature
• Vehicle at idle and under load
The intake valve for cylinder 6 is located in the engine's cylinder head.
Q: Can I drive with a P349D code?
A: It's not recommended to drive for extended periods with this code, as it may lead to engine damage.
Q: How do I know if my intake valve is faulty?
A: Symptoms include rough idling, engine misfires, and reduced power.
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